RCW 82.04.210 "By-product."
"By-product" means any additional product, other than the principal or intended product, which results from extracting or manufacturing activities and which has a market value, without regard to whether or not such additional product was an expected or intended result of the extracting or manufacturing activities.
[ 1961 c 15 § 82.04.210. Prior: 1955 c 389 § 22; prior: 1949 c 228 § 2, part; 1945 c 249 § 1, part; 1943 c 156 § 2, part; 1941 c 178 § 2, part; 1939 c 225 § 2, part; 1937 c 227 § 2, part; 1935 c 180 § 5, part; Rem. Supp. 1949 § 8370-5, part.]